Getting pid

(use '[me.raynes.conch.low-level :as sh2])
(def p (sh2/proc "sleep" "1000"))
(def pid (.getDeclaredField (.getClass (:process p)) "pid"))
(.setAccessible pid true)
(.getInt pid)
;; IllegalArgumentException No matching field found: getInt for class java.lang.reflect.Field  clojure.lang.Reflector.getInstanceField (Reflector.java:271)